A problematic weak layer has potential to surprise riders in features where a cohesive slab has formed over it.
A widespread crust with weak grains overtop is buried 30-70 cm deep. This problem is specific to areas where a cohesive slab has formed over the layer, such as wind-loaded lee features.
Our field team observed several slab avalanches up to size 2 in the Telkwas on Monday, mostly in wind-loaded lees, all running on the December crust.
A dusting of new snow blankets heavily wind-affected surfaces in the alpine and at treeline. Pockets of soft snow can be found in sheltered, lower angle terrain.
A significant weak layer is just reaching threshold with 30 to 70 cm of snow sitting above it, depending on wind loading patterns. The layer involves weak grains of surface hoar and facets sitting over a hard crust. This layer is likely to persist as an avalanche problem as it gets buried deeper.
The remainder of the snowpack is well settled and bonded.
Monday night
Mainly cloudy. Isolated flurries with minimal accumulation. <20 km/h variable wind. Treeline temperature -9 °C.
Tuesday
Cloudy. Isolated flurries with minimal accumulation. 20 to 40 km/h southeast wind. Treeline temperature -12 °C.
Wednesday
Mostly sunny. 20 to 40 km/h east wind. Treeline temperature -15 °C.
Thursday
Cloudy. Isolated flurries with minimal accumulation. 40 to 60 km/h south ridgetop wind. Treeline temperature -15 °C.
More details can be found in the Mountain Weather Forecast.
